I just found out my very good friend passed away several days ago. He was 53. His wife and him were on a cruise and she found him in their cabin on the floor. Last time I talked to him he was boasting how he was healthy as a horse and never had a thing wrong with him.
He and I have spent many many hours talking about what we would do during retirement, what we would go see, how we would spend the average day, everything. Our wives always teased us that the first one to say the "R" word when we got together had to buy a round. He was about a year away from FIRE.
Don't ever let your fears stop you from your dreams. There is no scheduled end date. I will miss him dearly.